Can a Pope resign? History says yes

Pope Benedict XVI waves to worshippers as he arrives at St. Peter's Square on December 29, 2012

Pope Benedict XVI waves to worshippers as he arrives at St. Peter's Square on December 29, 2012. The pontiff say he will resign on February 28 because his age prevented him from carrying out his duties, an unprecedented move in the modern history of the Catholic Church

News of the pope's resignation Monday shocked the world, including the pre-dominantly Catholic Philippines, which has not seen a papal resignation in ages.

Pope Benedict XVI said he will step down from his seat in the Vatican Feb. 28, noting that he lacked strength to fulfill his duties.

The pontiff, born as Joseph Aloisius Ratzinger in Germany, took the Vatican throne at the age of 78, 20 years older than his predecessor Pope John Paul II.

"For this reason, and well aware of the seriousness of this act, with full freedom I declare that I renounce the ministry of Bishop of Rome, Successor of Saint Peter," the pope said according to a Vatican statement.

But this is not the first time that a pope resigned, with a provision in the Code of Canon Law allowing such action.

Rule 332.2 of the code said: "If it happens that the Roman Pontiff resigns his office, it is required for validity that the resignation is made freely and properly manifested but not that it is accepted by anyone."

British Catholic weekly journal The Tablet, meanwhile, noted that there have been "at least four and possibly six" papal resignations.

The last pope to have resigned is Gregory XII, who stepped down in 1415 as part of negotiations at the Council of Constance during which there were two claimants to the papacy.